Yellowtail damselfish
Chrysiptera parasema
Blue damsel with a yellow tail; may strongly chase newcomers. A small but territorial damselfish. Its modest size does not automatically make it suitable for a small community aquarium.
At a glance
- Scientific name
- Chrysiptera parasema
- Dutch name
- Geelstaartjuffer
- Water temperature
- 24–26 °C
- pH
- 8.1–8.3
- Adult length, up to approximately
- 7.6 cm
- Experience
- Some experience
- Carbonate hardness (KH)
- 8–12 °dKH
- Specific gravity (SG)
- 1.024–1.025
- Starting volume
- 120 L
- Swimming or living zone
- Rocks & refuges
- Flow
- Moderate, with sheltered areas
- With corals
- Usually possible; check companions
This is a documented adult size, not a measured average. SL means body length excluding the tail fin. Sex, origin and cultivated form can affect size.
Care guidance; origin and captive breeding can change requirements. Some ranges are deliberately narrower than natural extremes in the source. Adjust water gradually and keep ammonia and nitrite at zero.
General marine targets also use group-level care guidance. Check the needs of your corals too. SG is not salinity in ppt; follow your instrument’s temperature calibration.
Tank sizes are editorial starting points for adults, not guarantees for a complete stocking plan. Group size, tank height, swimming length and territories may require a larger aquarium.
Origin
Indo-Pacific region
Habitat & setup
Tropical reef with rocks, crevices and open water.
Diet
Varied complete marine food and small thawed animal foods; include suitable plant-based food.
Behaviour & grouping
Prefer one specimen per territory; pairs only when demonstrably compatible.
Living with other animals
Only suitable, resilient companions with ample room and cover. Do not casually add conspecifics or similar species.
Reproduction
Egg-laying; raising marine larvae requires separate facilities and suitable tiny food.
A suitable cover helps prevent escape and jumping. Protect intakes for small animals. Do not use copper-based fish medication with invertebrates.
Sources & image credits
Data compiled on: 2026-09-27. Species sources support identity and care; group sources give general starting points. Practical recommendations are an editorial synthesis.
Photo: Chrysiptera_parasema.JPG — Brian Ong. CC BY-SA 3.0.